you can move your wardrobe slowly away from cotton. going out and replacing your whole wardrobe at once is quite expensive and unnecessary but if you replace your cotton when it wears out or goes out of fashion or for whatever excuse you use to replace them anyway. IIRC you live in So. Cal. as such you aren't likely to find too many really cold situations. Heavy wool is probably not soo important. I would think that light wool shirts would be a good item for the BOB light wool pants also. I also have a polypro union suit. This plus the wool shirt and pants is good enough for me down to about 30 if there is no wind. add a wind proof layer and I am fine to around 0 while moving and 20 sitting. You can replace the cotton skivys with silk or polypro depending upon your preference for feel against you skin. polypro will feel more like cotton. For damp I am firmly convinced that nothing beats wool. among the wools virgin merino for socks and skivys, hard worsted lambswool or sheltland for pants, & shirts and jackets, nothing beats alpaca for sweaters or blankets. Don't bother with angora - very warm but way too fragile. Wool works well in hot to cold weather and everything in-between if you are carrying the right weight of wool. light wool that isn't worsted is very wind permeable and will be quite cool and dry fast. Works great in warm weather. Heavy worsted wool will be fairly wind resistant and will keep you warm in the coldest environs even when wet.<br><br>Water? Carry as much as you need to stay hydrated between refill locations. If your in an urban setting you can refill your water carrier frequently then a quart soda bottle would be quite enough. If you are walking through the desert then discard anything you have to in order to carry as much water as you can. Don't let yourself become dehydrated it will make you stupid and dis-oriented and much more susceptable to hypothermia and other bad things.<br><br>Food. Don't worry about at all for a forced hike to safety. If you are less than a day from your destination and know that it is safe and stocked then just grab a small baggy of GORP and start walking. You won't want to slow down enough to fix a meal. Just get to your safe location and then eat the stock that is there. Carrying enough food for any length of time implies that you don't have a safe location and are meerly living on the move. living on the move will lead to hunter - gather behavior sooner or later - make it sooner and prepare the skills and knowledge of the local flora / fauna that will allow you to gather rather than carry food. 2000 calories is considered an adult intake as stated on the side of the morning cereal box. Recommended daily allowances are calculated from there. Nutrition is much more than calories. The nutrition needed while exerting yourself understressful situations carrying a pack and moving fast is vastly different from what you need while sitting on the couch exercising your fingers on the TV remote. Seek professional advise either in the library or at the Doc's office. Nutrition can also be quite personal. A diabetic needs different nutrition than a pregnant woman or a very thin athlete or a stocky middle-aged man such as myself.<br><br>As for packs I perfer an external frame with a big sack. The frame ensures that whatever I stuff in the big sack it will ride pretty much the same on my back, The big sack allows me to just stuff things in and go. I usually use smaller sacks in the bigger sack to seperate dirty from clean, kitchen from wardrobe, etc. I color code the smaller sacks and usually load them in a specific order. I tie tent, sleeping bag and mat, climbing ropes, extra footwear such as extra hiking boots, snow-shoes, skis on the outside rather than trying to have a large enough pack to hold them. IMHO, the strenghth of the packs construction is much more important thant the nifty configuration of pockets and accessories. That being said, I carry a camelback daypack on short hikes, a medium alice pack on overnights and keep some large military rucksacks packed for myself, my wife and each of our kids as BOB's <br>I envision the BOB's will hopefully be riding in the jeep but if things are bad enough to prevent automotive travel the rucksacks will be easier to carry than duffles. It will be heavy slow going but it will be going.